Gwen Stefani Calls Son Zuma Her 'Twin' in Birthday Tribute: 'Can't Believe You Are 12 Years Old'

Gwen Stefani

Happy birthday, Zuma!

Gwen Stefani’s son turned 12 on Friday, and the "No Doubt" singer marked the occasion with a sweet Instagram tribute.

“Happy birthday to my ZUMA I can’t believe u r 12 years old today!! we love u sooooooo much!! Gx,” Stefani wrote alongside several pictures of him.

The mother of three, 50, also added photos to her Instagram Story, revealing that Zuma looks a lot like Stefani did when she was his age. She wrote that she and Zuma are “twins,” sharing two photos of her with her middle child — one which was taken recently and one comparing pictures of them at similar ages.

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Gwen Stefani

RELATED: Gavin Rossdale Reveals Son Zuma, 11, Broke Both His Arms Within a 6-Week Span: 'He's So Brave'

Gwen Stefani

Stefani shares Zuma with ex-husband Gavin Rossdale, along with sons Apollo Bowie Flynn, 6, and Kingston James McGregor, 14. Her boyfriend, fellow Voice judge Blake Shelton, also helps raise the three boys.

Last month, Shelton, 44, opened up about the balance of being both a friend and a role model to his girlfriend's sons.

"That's a scary moment for me because it's one thing for me to be with the kids all the time and be their buddy, but you do have to consider after a while that they start to listen to things that you say. There's a lot of responsibility that comes with that," Shelton told Today, referring to his sweet Father's Day tribute from Stefani in June.

RELATED: Blake Shelton on the Balance of Being Both a 'Buddy' and Parental Figure to Gwen Stefani's Sons

Gwen Stefani/Instagram Blake Shelton with Gwen Stefani and her sons Kingston (L) and Zuma

Stefani shared a collection of images on Instagram of her boyfriend Shelton spending time with all three boys over the years. "Happy father’s day @blakeshelton thank u for helping me raise these boys!! #weloveyou! G❤️K❤️Z❤️A gx," she wrote in the post's caption.

While social distancing together on Shelton's ranch in Oklahoma amid the coronavirus pandemic, Shelton, Stefani, Apollo, Zuma and Kingston have spent time "doing things that I wished I had time to do for the last 20 years."

"That's literally stupid things, like pick blackberries," Shelton told Today's Hoda Kotb and Carson Daly. "We grew a garden, grew several acres of sweet corn."